Inside Health

For Chronic Fatigue, Placebos Fail the Test

By NICHOLAS BAKALAR

Published: March 29, 2005

Many doctors believe that sugar pills are likely to be effective for patients with chronic fatigue syndrome, trusting that a placebo will help relieve the mental and physical exhaustion that characterize the illness.

But a new study has found that people who have the syndrome respond at a lower rate to placebos than patients with other diseases. The paper was published in the March-April issue of Psychosomatic Medicine.

Studies suggest that placebos relieve the symptoms for about 30 percent of patients suffering from a wide variety of illnesses. Migraine headaches, for example, respond at a rate of about 29 percent to placebo treatment, major depression at about 30 percent and reflux esophagitis at about 26 percent.

In some diseases, placebo treatments are even more effective -- 36 to 44 percent of patients with duodenal ulcers improve on placebos, depending on how many of the treatments are offered each day.

But by pooling results from more than two dozen studies, the researchers, led by Dr. Hyong Jin Cho, a professor of psychiatry at King's College London, found that, among people with chronic fatigue syndrome, only 19.6 percent responded to placebos, not the 50 percent found by previous, less systematic studies.

To Dr. Cho, the results were both unexpected and disappointing: he says he believes placebos can be a legitimate and useful form of medical treatment. He concluded not that placebos were unhelpful in treating chronic fatigue but that their use should be perfected.

To many doctors, chronic fatigue syndrome seems like a perfect candidate for placebo treatment, Dr. Cho and his colleagues write. Its symptoms are often indistinct: in addition to general fatigue, patients complain of muscle and joint pain, headaches, memory impairment and mood disturbances. Moreover, the symptoms frequently fluctuate over time, and they are more acute when the patients are paying close attention to them.

The illness has no cure, and the Centers for Disease Control and Prevention estimates that as many as 500,000 Americans suffer from it.

Dr. Cho and his colleagues speculate that the skepticism about the illness on the part of health care professionals may damage the trust between doctor and patient -- a factor that may influence the effect of a placebo.

According to the study, placebos presented as medical or alternative-complementary treatments have a greater effect with chronic fatigue patients than do those offered as psychiatric interventions. The researchers suggest that this may be because most patients have a firm prior belief that the illness is physical. They make no judgment about the accuracy of that belief.

But Dr. Brian Fallon, an associate professor of psychiatry at Columbia University, offers a different interpretation. The fact that chronic fatigue syndrome responds so poorly to placebo treatment, he said, provides evidence that the syndrome has a physiological basis, though one that is still poorly understood.

''The finding by Dr. Cho and colleagues will come as no surprise to patients with C.F.S. who experience debilitating fatigue despite numerous treatment interventions,'' Dr. Fallon said. ''That the placebo response in C.F.S. was far lower that in primary psychiatric disorders such as depression highlights the distinct nature of C.F.S. and how little we know.''

Whatever conclusions may be drawn from the study's results, Dr. Cho says he sees placebo treatments as important.

''Many alternative therapies may provide a cure that depends on this powerful placebo effect,'' he said in an e-mail message. ''I'm not using the term pejoratively, since empathy and time spent with the patient by the professionals in this area are indeed of important therapeutic value.''